Carbon and nitrogen isotope signals in eel bone collagen from Mesolithic and Neolithic sites in northern Europe

Carbon and nitrogen isotope analysis was undertaken on collagen extracted from eel bone from six Mesolithic and Neolithic sites in northern Europe. The results were compared with data obtained on other archaeological fish remains and modern eel caught in fresh and brackish water and from the sea. The possibility of discriminating between freshwater, brackish and marine signals in archaeological eel bone is evaluated and the implications for archaeology discussed. Our data suggest that eel found at coastal Mesolithic and Neolithic sites have carbon isotope signals consistent with a marine origin with no evidence of freshwater residency. The sample of eel bone from one inland site is small but indicates carbon isotope values more consistent with freshwater residency or at least values intermediate between freshwater and marine carbon pools.     

Neural Network Modeling of Constrained Spatial Interaction Flows: Design, Estimation, and Performance Issues

In this paper a novel modular product unit neural network architecture is presented to model singly constrained spatial interaction flows. The efficacy of the model approach is demonstrated for the origin constrained case of spatial interaction using Austrian interregional telecommunication traffic data. The model requires a global search procedure for parameter estimation, such as the Alopex procedure. A benchmark comparison against the standard origin constrained gravity model and the two–stage neural network approach, suggested by Openshaw (1998), illustrates the superiority of the proposed model in terms of the generalization performance measured by ARV and SRMSE.     

Geoarchaeological tsunami deposits at Palaikastro (Crete) and the Late Minoan IA eruption of Santorini

The explosive eruption at Santorini in the Aegean Sea during the second millennium BCE was the largest Holocene volcanic upheaval in the Eastern Mediterranean region. The eruption was disastrous for the Minoan settlements at Santorini, but the effect on human society in the neighbouring islands and regions is still clouded in uncertainty. Tsunami generation was suggested, but comparatively little evidence was found. The lack of firm tsunami traces is particularly puzzling in Crete with its coastal settlements of the Late Minoan IA period, during which the Santorini eruption occurred. Here, we report the discovery of extensive geoarchaeological tsunami deposits at Palaikastro in north-eastern Crete. These deposits are characterized by a mixture of geological materials, including volcanic Santorini ash, and archaeological settlement debris. Various tsunami signatures were identified: (1) erosional contact with the underlying strata, (2) volcanic ash intraclasts in the lower part of the deposit, (3) reworked building stone material in the lower part of the deposit, (4) individual marine shells, (5) marine micro-fauna, (6) imbrication of rounded beach pebbles, settlement debris, ceramic sherds and even bones, (7) multi-modal chaotic composition. Late Minoan human settlement activities at Palaikastro provided architectural and stratigraphic frameworks in space and time that recorded and preserved tsunami evidence as geoarchaeological deposits. Such stratigraphic resolution and preservation may not occur in the natural landscape. Volcanic ash transported by wind from Santorini south-east to Crete preceded the tsunami. Geological, archaeological and radiocarbon dating criteria all converge, indicating that the tsunami deposits are coeval with the Minoan Santorini eruption. Field evidence suggests that tsunami waves at Palaikastro were at least 9 m high. Inverse tsunami modeling was attempted, based on these newly discovered tsunamigenic deposits. The initial wave in the generation region at Santorini that best fits the stratigraphic data is a wave with +35 to −15 m initial amplitude and a crest length of about 15 km.     

Telephone Communication Patterns in Austria: A Comparison of the IPFP-based Graph-Theoretic and the Intramax Approaches

Two alternative methodological approaches (the IPFP-based and the intramax procedures) to the problem of pattern identification in spatial interaction data are compared and evaluated in this paper. After a general discussion of the major characteristics and shortcomings of these methodologies, the paper presents the findings of a case study relying on telecommunication data measured by the Austrian PTT in 1991, in terms of erlangs. The results clearly illustrate the superiority of the intramax approach in the context of medium-sized and relatively centralized flow systems.     

Mineralogical and geochemical characterization of high-medieval lead–silver smelting slags from Wiesloch near Heidelberg (Germany)—an approach to process reconstruction

Here, we present detailed electron microprobe analyses and age data of high-medieval lead–silver smelting slags. The mineral composition data provide a database of all silicate and oxide phases in the slag. Bulk chemistry as well as mineral composition is used to reconstruct liquidus, solidus, and viscosity of the slag melt. By calculating the mass balance of the smelting process, a mass ratio of the various compounds used in the smelting process is determined. Through this we were able to discriminate qualitatively between non-ferrous metal smelting slags and bloomery slags. We also report a new type and process of silver production in which argentiferous galmei (zinc carbonate) was used as a main silver ore together with galena. The results indicate a sophisticated high-medieval smelting technology, in which a slag with a low liquidus and a low viscosity was created.